The present invention relates to a semiconductor module having a plurality of mutually electrically connected semiconductor devices arranged on a wiring board, and in particular to a wiring board and a wiring method for such a semiconductor module.
It is a recent trend that semiconductor devices are packaged to form a longitudinally long (rectangular) shape in order to achieve high performances. For this reason, it is difficult to produce semiconductor module by arranging a quantity of semiconductor devices specified by standards or the like on a wiring board with a shape specified by the specifications or a customer request.
One of measures proposed to avoid this problem is a method of arranging a plurality of semiconductor devices alternately lengthwise and crosswise while changing alternately their orientations by 90 degrees.
On the other hand, various wiring methods have been proposed to eliminate the signal-to-signal skew (for example, Japanese Patent Laid-Open Publication No. H11-163531 (Patent Document 1), No. 2000-082743 (Patent Document 2), No. 2004-096095 (Patent Document 3), and No. H11-340438 (Patent Document 4)).